Field of the Invention
The present invention relates to a hydraulic tube for a vehicle, and more particularly, to a hydraulic tube which has improved performance for preventing oil leakage.
Description of Related Art
Referring to FIG. 1, a clutch system using hydraulic power employs a hydraulic tube 10 which transfers hydraulic power from a clutch master cylinder 1 to a release cylinder 3.
Referring to FIGS. 2A and 2B, the hydraulic tube 10 of the related art includes a pipe 11 made of steel, a connector 12 made of plastic which is fitted into and coupled with the pipe 11, and a sealer 13 made of rubber which is fitted into one end of the pipe 11 and is coupled with one end of the connector 12.
For the coupling between the pipe 11 and the connector 12, a pipe rib 11a having a triangular cross-section protrudes outward from the pipe 11, and a connector groove 12a is formed in the inner circumference of the connector 12 such that the pipe rib 11a is fitted into the connector groove 12a. The connector 12 also has a plurality of slots 12b on the outer circumference. The slots 12 are opened in the longitudinal direction of the connector 12.
The connector 12 is spread outwards at the slots 12b when the pipe 11 is being fitted into the connector 12. When fitting the pipe rib 11a into the connector groove 12a is completed, the pipe 11 and the connector 12 are assembled together while the connector 12 restores the original position from the outwardly spread position.
In addition, for the assembly between the connector 12 and the sealer 13, a connector rib 12c protrudes outward from the outer circumference of one end of the connector 12, and a sealer groove 13a is formed in the inner circumference of the sealer 13 such that the connector rib 12c is fitted into the sealer groove 13a. An inner rib 13b is formed on the inner circumferential portion of the sealer 13 from the sealer groove 13a to one end of the sealer 13 such that the inner rib 13b adjoins to the pipe 11.
The conventional hydraulic tube 10 is configured such that the connector 12 has the plurality of slots 12b. However, the slots 12b reduce the structural strength of the connector 12 which is made of plastic, which is problematic. In particular, this makes a mold for insert molding more complicated and increases cost.
In addition, in the conventional hydraulic tube 10, the connector 12 is spread outwards along the slots 12b when the connector 12 is being fitted around the pipe 11. When the connector 12 is permanently deformed in this process, a gap is formed between the pipe 11 and the connector 12, which disadvantageously leads to an oil leakage.
Furthermore, since the assembly between the pipe 11 and the connector 12 is accomplished by the pipe rib 11a and the connector groove 12a, the connector groove 12a is a factor that locally lowers the strength of a portion of the connector groove 12a when the pipe 11 and the connector 12 are assembled together. This consequently causes a permanent deformation in the portion of the connector groove 12a when the pipe 11 and the connector 12 are assembled together, which disadvantageously leads to an oil leakage.
In addition, while the overall sealing performance of the hydraulic tube 10 is determined by the contact portions of the pipe 11 and the sealer 13, the conventional sealing structure provides a seal by bringing only the inner rib 13b of the sealer 13 into the contact with the pipe 11. This structure of sealing the hydraulic tube 10 using the single contact structure of the inner rib 13b has an insignificant oil leak prevention effect, which is problematic.
Among the reference numerals that have not been described, the reference numeral 3 indicates a clutch pedal, and the reference numeral 4 indicates a manual transmission.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.